Newcomb’s Problem

In an alternate universe, on an alternate earth, all smokers, and only smokers, get brain cancer. Everyone enjoys smoking, but many resist the temptation to smoke, in order to avoid getting cancer. For a long time, however, there was no known cause of the link between smoking and cancer.

Twenty years ago, autopsies revealed tiny black boxes implanted in the brains of dead persons, connected to their brains by means of intricate wiring. The source and function of the boxes and of the wiring, however, remains unknown. There is a dial on the outside of the boxes, pointing to one of two positions.

Scientists now know that these black boxes are universal: every human being has one. And in those humans who smoke and get cancer, in every case, the dial turns out to be pointing to the first position. Likewise, in those humans who do not smoke or get cancer, in every case, the dial turns out to be pointing to the second position.

It turns out that when the dial points to the first position, the black box releases dangerous chemicals into the brain which cause brain cancer.

Scientists first formed the reasonable hypothesis that smoking causes the dial to be set to the first position. Ten years ago, however, this hypothesis was definitively disproved. It is now known with certainty that the box is present, and the dial pointing to its position, well before a person ever makes a decision about smoking. Attempts to read the state of the dial during a person’s lifetime, however, result most unfortunately in an explosion of the equipment involved, and the gruesome death of the person.

Some believe that the black box must be reading information from the brain, and predicting a person’s choice. “This is Newcomb’s Problem,” they say. These persons choose not to smoke, and they do not get cancer. Their dials turn out to be set to the second position.

Others believe that such a prediction ability is unlikely. The black box is writing information into the brain, they believe, and causing a person’s choice. “This is literally the Smoking Lesion,” they say. Accepting Andy Egan’s conclusion that one should smoke in such cases, these persons choose to smoke, and they die of cancer. Their dials turn out to be set to the first position.

Still others, more perceptive, note that the argument about prediction or causality is utterly irrelevant for all practical purposes. “The ritual of cognition is irrelevant,” they say. “What matters is winning.” Like the first group, these choose not to smoke, and they do not get cancer. Their dials, naturally, turn out to be set to the second position.